Spinning of viscose



United States Patent SPINNING 0F VISCOSE Robert A. (llney, Wilmington, Del., assignor to Atlas Chemical Industries, Inc., Wilmington, Del, a corporation of Pennsylvania No Drawing. Filed Jan. 21, 1960, Ser. No. 3,713 7 Claims. (Cl. 106165) This invention relates to the regeneration of cellulose solutions and more particularly the manufacture of regenerated cellulose articles such as yarn and film from viscose.

It is an object of the present invention to provide a process for producing high-tenacity regenerated cellulose yarn having novel and desirable properties.

Another object of the invention is to provide a process for producing highetenacity regenerated cellulose yarn.

A further object is to provide a process whereby unripened viscose can be spun to produce high-tenacity, fatigue resistant regenerated cellulose fiber having improved soil and abrasion resistance.

A still further object is to provide novel viscose compositions adapted to the spinning of high-tenacity regenerated cellulose yarns.

The above and other objects will become more apparent in the course of the following description of the invention and in the appended claims.

The above objects are accomplished in accordance with the invention by incorporating in the viscose solution to be spun a compound which is a quaternary ammonium compound of a substituted imidazoline of the formula H(OCHzCHi)r-OCH2OH2N N CH2 (!7H2 where R is an alkyl or alkenyl radical containing from 11; to 20 carbon atoms and x is from 1 to 100. Illustrative of the substituted imidazolines which may be quaternized to form the viscose additive of the invention are those in which R of the hereinabove formula is heptadecenyl and x is 50; R is heptadecyl and x is 75; R is undecyl and x is 20; etc.

The viscose additives are substituted imidazolines as above-defined and illustrated which have been converted to quaternary ammonium salts as by reaction with conventional quaternizing agents such as dimethyl sulfate, diethyl sulfate, alkyl chlorides, benzyl chlorides, diethyl phosphate, epichlorohydrin and the like.

The hereinabove defined compounds are soluble in viscose solutions and may be incorporated therein at any stage of the viscose process after the cellulose is dissolved. For effective results, from about 0.5% to about 4.0% by weight of the quaternary ammonium salt of the substituted imidazoline based on the weight of the cellulose in the solution is employed. The composition of the viscose may vary Widely as is known in the art. It may be formed, for example, from cotton linters or from wood pulp as the source of cellulose and may contain from 4% to of cellulose in a solution containing from 4% to 8% of alkali metal hydroxide. The amount of carbon disulfide used in xanthation may be from 25% to 50%.

The viscose solutions of the invention, i.e. those containing the quaternary ammonium salt of a substituted imidazoline hereinabove defined, may be employed in the normal manner for the production of regenerated cellulose films and yarns. Suitable spinning or regenerating baths contain sulfuric acid, zinc sulfate and sodium sulfate. Preferred spinning baths contain from 4% to 12% sulfuric acid, from 1% to 10% zinc sulfate and from 13% to 25 sodium sulfate.

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The defined compounds useful in the practice of the present invention are readily prepared by the addition of ethylene oxide to a substituted imidazoline followed by conversion of the ethylene oxide adduct to a quaternary ammonium salt.

The following nonlimiting examples illustrate the preparation of viscose solutions and the production of regenerated cellulose yarn therefrom, both in accordance with the practice of the present invention.

Example I Introduce 407 grams of 1-hydroxyethy1-Z-heptadecenyl imidazoline and 5.2 grams of sodium hydroxide into an autoclave provided with a stirrer and a coil for circulating heat exchange fluid therein. Flush the autoclave with ethylene oxide gas and close. Heat the charge to 145 C. and add, in increments, 2200 grams of ethylene oxide; controlling the rate of addition, and the rate of heat exchange to maintain the temperature at 145 C. and the pressure between 30 and 50 pounds per square inch. After all of the ethylene oxide has been added continue the reaction at 145 C. until the ethylene oxide is consumed as indicated by the decrease of pressure to substantially atmospheric. The resultant product is a highboiling liquid containing approximately 51 oxyethylene groups per imidazoline residue and is a surface-active A cotton linters viscose containing 7% cellulose and 6.6% sodium hydroxide is prepared in the conventional manner except that during the dissolution of xanthated cellulose in aqueous sodium hydroxide, 1% by weight based on the cellulose of the diethyl sulfate quaternary ammonium salt of 1-polyoxy-ethylene-Z-heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline prepared in Example I is added and thoroughly dispersed therein. The resultant viscose solution is spun in an unripened salt (high salt index of 7) into a bath of 7% sulfuric acid, 8% zinc sulfate and 17% sodium sulfate. The spinning is carried out on conventional equipment to produce regenerated cellulose yarn of high tensile strength resistant toflexing and abrasion.

Example III Introduce 285 grams of l-hydroxyethyl-Z-undecyl imidazoline and 1.5 grams of sodium hydroxide into an autoclave provided with a stirrer and a coil for circulating heat exchange fluid therein. :Flush the autoclave with ethylene oxide gas and close. Heat the charge to 145 C. and add, in increments, 440 grams of ethylene oxide; controlling the rate of addition and rate of heat exchange to maintain the temperature at 145 C. and the pressure between 30 and 50 pounds per square inch. After all of the ethylene oxide has been added continue the reaction at 145 C. until the ethylene oxide is consumed as indicated by the decrease of pressure to substantially atmospheric. The resultant product is a highboiling liquid containing approximately 10 oxyethylene groups per imidazoline residue and is a surface-active agent readily dispersible in water.

The polyoxyethylene undecyl imidazoline as prepared above was reacted at a temperature of C. to C. with benzyl chloride for 2 hours. The quaternary ammonium compound formed was a pasty solid readily soluble in water.

3 Example IV A viscose containing 7% cellulose and 6% sodium hydroxide is modified by the addition of 2% by weight based on the cellulose of the benzyl chloride quaternary ammonium salt of l-polyoxyethylene-2-undecyl imidazoline containing oxyethylene groups per mol of imidazoline as prepared in Example III. The modified viscose solution is spun on conventional equipment into a bath of 8% sulfuric acid, 8% zinc sulfate, and 20% sodium sulfate. Yarns of smooth surface and high tensile strength resistant to soiling result.

Example V Introduce 386 grams of 1-hydroxyethyl-2-heptadecyl imidazoline and 7.4 grams of sodium hydroxide into an autoclave provided with a stirrer and a coil for circulating heat exchange fluid therein. Flush the autoclave with ethylene oxide gas and close. Heat the charge to 145 C. and add, in increments, 3300 grams of ethylene oxide; controlling the rate of addition and rate of heat exchange to maintain the temperature at 145 C. and the pressure between 30 and 50 pounds per square inch. After all of the ethylene oxide has been added, continue the reaction at 145 C. until the ethylene oxide is consumed as indicated by the decrease of pressure to substantially atmospheric. The resultant product is a highboiling liquid containing approximately 75 oxyethylene groups per imidazoline residue and is a surface-active agent, readily dispersible in Water.

The hereinabove prepared polyoxyethylene heptadecyl imidazoline was reacted at a temperature of from 75 C. to 100 C. The quaternary ammonium compound formed was a pasty solid readily soluble in water.

Example VI A wood pulp viscose containing 7% cellulose and 6.6% sodium hydroxide is prepared in the conventional manner except that 1% by weight based on the cellulose of the epichlorohydrin quaternary ammonium salt of 1- polyoxyethylene-Z-heptadecyl imidazoline containing 51 oxyethylene groups per mol of heptadecyl imidazoline as prepared in Example V is incorporated therein during the dissolution of the xanthate in alkali solution. Using conventional spinning equipment the not fully ripened viscose is coagulated and regenerated by spinning into a bath containing 8% sulfuric acid, 8% zinc sulfate, and 20% sodium sulfate. The regenerated purified cellulose filaments are exceptionally strong, abrasion resistant and soil resistant.

What is claimed is:

1. Viscose containing from 0.5% to 4.0%, based on the cellulose content of the viscose, of a quaternary ammonium compound of 1) an ester of a lower alcohol and an inorganic acid and (2) a substituted imidazoline conforming to the generic formula where R is a member selected from the group consisting of alkyl and alkenyl radicals of from 11 to 20 carbon atoms and x has any value from 1 to 100.

2. Viscose containing from 0.5% to 4.0%, based on the cellulose content of the viscose, or" the diethyl sulfate quaternary ammonium salt of l-polydxyethylene-Z- heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline.

3. A viscose spinning solution comprising from 4.0% to 10.0% cellulose, from 4.0% to 8.0% alkali metal hydroxide and from 0.5% to 4.0% based on the weight of the cellulose of the diethyl sulfate quaternary ammonium salt of 1-polyoxyethylene-Z-heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline.

4. In the spinning of regenerated cellulosic yarns from viscose, the improvement which comprises dissolving in the viscose solution from 0.5% to 4.0%, based on its cellulose content of the diethyl sulfate quaternary ammonium salt of 1-polyoxyethyleue-Z-heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline.

5. A method of producing regenerated cellulosic structures which comprises spinning into an acid regenerating bath a viscose containing in solution from 0.5 to 4.0% based on the weight of cellulose of the diethyl sulfate quaternary ammonium salt of l-polyoxyethylene-Z- heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline.

6. A method of producing regenerated cellulosic structures which comprises spinning a viscose solution containing from 4.0% to 10.0% cellulose, from 4.0% to 8.0% alkali metal hydroxide and from 0.5% to 4.0%, based on the cellulose, of the diethyl sulfate quaternary ammonium salt of 1-polyoxyethylene2-heptadecenyl imidazoline containing 51 oxyethylene groups per mol of heptadecenyl imidazoline.

7. Viscose containing from 0.5% to 4.0% based on cellulose content of the viscose of a quaternary ammonium compound of 1) an ester of a lower alcohol and an inorganic acid and (2) a substituted imidazoline conforming to the generic formula References Cited in the file of this patent UNITED STATES PATENTS Schlatter Sept. 15, 1959 Limburg et al. Apr. 4, 1961 OTHER REFERENCES Elod et al.: Reyon Zellwolle und Andere Chemicfastern, Jahrg. 1955, No. 33, page 322 (Type IV). 

1. VISCOSE CONTAINING FROM 0.5% TO 4.0%, BASED ON THE CELLULOSE CONTENT OF THE VISCOSE, OF A QUATERNARY AMMONIUM COMPOUND OF (1) AN ESTER OF A LOWER ALCOHOL AND AN INORGANIC ACID AND (2) A SUBSTITUTED IMIDAZOLINE CONFORMING TO THE GENERIC FORMULA 